Re: [PATCH 1/2] dt-bindings: mtd: nand: Macronix: document new binding

From: Florian Fainelli
Date: Tue May 16 2023 - 14:58:55 EST


+William,

On 5/16/23 11:55, Álvaro Fernández Rojas wrote:
Hi Jaime,

I've reproduced the issue on a Comtrend VR-3032u (MX30LF1G08AA). After
forcing it to check block protection (it's not supported on that
device), the NAND controller stops reading/writing anything.

@Florian is it possible that low level ops (GET_FEATURES/SET_FEATURES)
aren't supported on BCM63268 NAND controllers and this is causing the
issue?

Yes, this looks like what we have seen as well even with newer NAND controllers actually. Would it be possible to obtain a full log from either of you?

William, is this something you have seen before as well?


Best regards,
Álvaro.

El mié, 26 abr 2023 a las 9:24, liao jaime (<jaimeliao.tw@xxxxxxxxx>) escribió:

Hi Álvaro

In nand_scan_tail(), each manufacturer init function call will be execute.
In macronix_nand_init(), block protect will be execute after flash detect.
I have validate MX30LF1G18AC in Linux kernel v5.15.
I didn't got situation "device hangs" on my side.
BP is to prevent incorrect operations.
Please check the controller settings for tracing this issue.

Thanks
Jaime


Hello YouChing and Jaime,

I still didn't get any feedback from you (or Macronix) on this issue.
Did you have time to look into it?

Thanks,
Álvaro.

El vie, 24 mar 2023 a las 18:04, Álvaro Fernández Rojas
(<noltari@xxxxxxxxx>) escribió:

Hi Miquèl,

2023-03-24 15:36 GMT+01:00, Miquel Raynal <miquel.raynal@xxxxxxxxxxx>:
Hi Álvaro,

+ YouChing and Jaime from Macronix
TLDR for them: there is a misbehavior since Mason added block
protection support. Just checking if the blocks are protected seems to
misconfigure the chip entirely, see below. Any hints?

Could it be that the NAND is stuck expecting a read 0x00 command which
isn’t sent after getting the features?


noltari@xxxxxxxxx wrote on Fri, 24 Mar 2023 15:15:47 +0100:

Hi Miquèl,

2023-03-24 14:45 GMT+01:00, Miquel Raynal <miquel.raynal@xxxxxxxxxxx>:
Hi Álvaro,

noltari@xxxxxxxxx wrote on Fri, 24 Mar 2023 12:21:11 +0100:

El vie, 24 mar 2023 a las 11:49, Miquel Raynal
(<miquel.raynal@xxxxxxxxxxx>) escribió:

Hi Álvaro,

noltari@xxxxxxxxx wrote on Fri, 24 Mar 2023 11:31:17 +0100:

Hi Miquèl,

El vie, 24 mar 2023 a las 10:40, Miquel Raynal
(<miquel.raynal@xxxxxxxxxxx>) escribió:

Hi Álvaro,

noltari@xxxxxxxxx wrote on Thu, 23 Mar 2023 13:45:09 +0100:

Add new "mxic,disable-block-protection" binding documentation.
This binding allows disabling block protection support for
those
devices not
supporting it.

Signed-off-by: Álvaro Fernández Rojas <noltari@xxxxxxxxx>
---
Documentation/devicetree/bindings/mtd/nand-macronix.txt | 3
+++
1 file changed, 3 insertions(+)

diff --git
a/Documentation/devicetree/bindings/mtd/nand-macronix.txt
b/Documentation/devicetree/bindings/mtd/nand-macronix.txt
index ffab28a2c4d1..03f65ca32cd3 100644
--- a/Documentation/devicetree/bindings/mtd/nand-macronix.txt
+++ b/Documentation/devicetree/bindings/mtd/nand-macronix.txt
@@ -16,6 +16,9 @@ in children nodes.
Required NAND chip properties in children mode:
- randomizer enable: should be "mxic,enable-randomizer-otp"

+Optional NAND chip properties in children mode:
+- block protection disable: should be
"mxic,disable-block-protection"
+

Besides the fact that nowadays we prefer to see binding
conversions
to
yaml before adding anything, I don't think this will fly.

I'm not sure exactly what "disable block protection" means, we
already have similar properties like "lock" and
"secure-regions",
not
sure they will fit but I think it's worth checking.

As explained in 2/2, commit 03a539c7a118 introduced a regression
on
Sercomm H500-s (BCM63268) OpenWrt devices with Macronix
MX30LF1G18AC
which hangs the device.

This is the log with block protection disabled:
[ 0.495831] bcm6368_nand 10000200.nand: there is not valid maps
for
state default
[ 0.504995] nand: device found, Manufacturer ID: 0xc2, Chip ID:
0xf1
[ 0.511526] nand: Macronix MX30LF1G18AC
[ 0.515586] nand: 128 MiB, SLC, erase size: 128 KiB, page size:
2048, OOB size: 64
[ 0.523516] bcm6368_nand 10000200.nand: detected 128MiB total,
128KiB blocks, 2KiB pages, 16B OOB, 8-bit, BCH-4
[ 0.535912] Bad block table found at page 65472, version 0x01
[ 0.544268] Bad block table found at page 65408, version 0x01
[ 0.954329] 9 fixed-partitions partitions found on MTD device
brcmnand.0
...

This is the log with block protection enabled:
[ 0.495095] bcm6368_nand 10000200.nand: there is not valid maps
for
state default
[ 0.504249] nand: device found, Manufacturer ID: 0xc2, Chip ID:
0xf1
[ 0.510772] nand: Macronix MX30LF1G18AC
[ 0.514874] nand: 128 MiB, SLC, erase size: 128 KiB, page size:
2048, OOB size: 64
[ 0.522780] bcm6368_nand 10000200.nand: detected 128MiB total,
128KiB blocks, 2KiB pages, 16B OOB, 8-bit, BCH-4
[ 0.539687] Bad block table not found for chip 0
[ 0.550153] Bad block table not found for chip 0
[ 0.555069] Scanning device for bad blocks
[ 0.601213] CPU 1 Unable to handle kernel paging request at
virtual
address 10277f00, epc == 8039ce70, ra == 8016ad50
*** Device hangs ***

Enabling macronix_nand_block_protection_support() makes the device
unable to detect the bad block table and hangs it when trying to
scan
for bad blocks.

Please trace nand_macronix.c and look:
- are the get_features and set_features really supported by the
controller driver?

This is what I could find by debugging:
[ 0.494993] bcm6368_nand 10000200.nand: there is not valid maps for
state default
[ 0.505375] nand: device found, Manufacturer ID: 0xc2, Chip ID:
0xf1
[ 0.512077] nand: Macronix MX30LF1G18AC
[ 0.515994] nand: 128 MiB, SLC, erase size: 128 KiB, page size:
2048, OOB size: 64
[ 0.523928] bcm6368_nand 10000200.nand: detected 128MiB total,
128KiB blocks, 2KiB pages, 16B OOB, 8-bit, BCH-4
[ 0.534415] bcm6368_nand 10000200.nand: ll_op cmd 0xa00ee
[ 0.539988] bcm6368_nand 10000200.nand: ll_op cmd 0x600a0
[ 0.545659] bcm6368_nand 10000200.nand: ll_op cmd 0x10000
[ 0.551214] bcm6368_nand 10000200.nand: NAND_CMD_GET_FEATURES =
0x00
[ 0.557843] bcm6368_nand 10000200.nand: ll_op cmd 0x10000
[ 0.563475] bcm6368_nand 10000200.nand: NAND_CMD_GET_FEATURES =
0x00
[ 0.569998] bcm6368_nand 10000200.nand: ll_op cmd 0x10000
[ 0.575653] bcm6368_nand 10000200.nand: NAND_CMD_GET_FEATURES =
0x00
[ 0.582246] bcm6368_nand 10000200.nand: ll_op cmd 0x80010000
[ 0.588067] bcm6368_nand 10000200.nand: NAND_CMD_GET_FEATURES =
0x00
[ 0.594657] nand: nand_get_features: addr=a0 subfeature_param=[00
00 00 00] -> 0
[ 0.602341] macronix_nand_block_protection_support:
ONFI_FEATURE_ADDR_MXIC_PROTECTION=0
[ 0.610548] macronix_nand_block_protection_support: !=
MXIC_BLOCK_PROTECTION_ALL_LOCK
[ 0.624760] Bad block table not found for chip 0
[ 0.635542] Bad block table not found for chip 0
[ 0.640270] Scanning device for bad blocks

I don't know how to tell if get_features / set_features is really
supported...

Looks like your driver does not support exec_op but the core provides a
get/set_feature implementation.

According to Florian, low level should be supported on brcmnand
controllers >= 4.0
Also:
https://github.com/nomis/bcm963xx_4.12L.06B_consumer/blob/e2f23ddbb20bf75689372b6e6a5a0dc613f6e313/shared/opensource/include/bcm963xx/63268_map_part.h#L1597

Just to be sure, you're using a mainline controller driver, not this
one?

Yes, this was just to prove that the HW I’m using has get/set features support.
I’m using OpenWrt, so it’s linux v5.15 driver.




- what is the state of the locking configuration in the chip when
you
boot?

Unlocked, I guess...
How can I check that?

It's in your dump, the chip returns 0, meaning it's all unlocked,
apparently.

Well, I can read/write the device if block protection isn’t disabled,
so I guess we can confirm it’s unlocked…


- is there anything that locks the device by calling mxic_nand_lock()
?

So nobody locks the device I guess? Did you add traces there?

It doesn’t get to the point that it enabled the lock/unlock functions
since it fails when checking if feature is 0x38, so there’s no point
in adding those traces…

Right, it returns before setting these I guess.



- finding no bbt is one thing, hanging is another, where is it
hanging
exactly? (offset in nand/ and line in the code)

I've got no idea...

You can use ftrace or just add printks a bit everywhere and try to get
closer and closer.

I think that after trying to get the feature it just start reading
nonsense from the NAND and at some point it hangs due to that garbage…

It should refuse to mount the device somehow, but in no case the kernel
should hang.

Yes, I think that this is a side effect (maybe a different bug somewhere else).


Is it posible that the NAND starts behaving like this after getting
the feature due to some specific config of my device?


I looked at the patch, I don't see anything strange. Besides, I have a
close enough datasheet and I don't see what could confuse the device.

Are you really sure this patch is the problem? Is the WP pin wired on
your design?

There’s no WP pin in brcmnand controllers < 7.0

What about the chip?

Maybe it has a GPIO controlling that, but I don’t have that info…


Thanks,
Miquèl


--
Florian